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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>

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<script>
    let arr = [1, 7, 3, 5, 6];
    for (let i = 0; i < arr.length; i++) { //趟数
        for (let j = 0; j < arr.length - i - 1; j++) { //次数
            if (arr[j] < arr[j + 1]) {
                let temp;
                temp = arr[j];
                arr[j] = arr[j + 1];
                arr[j + 1] = temp;
            }
        }
    }
    console.log(arr)
</script>

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